nations, president obama will reiterate the u.s. commitment to preventing iran from acquiring a nuclear weapon. he'll also call on leaders in the combustible muslim world to end the violence and declare the u.s. will not shrink from bringing to justice those who harm americans. sensing an opening, mitt romney has been assailing the president for calling the situation bumps in the road. >> bumps in the road -- we had an ambassador assassinated. and iran is that much closer to building a nuclear weapon. >> reporter: the white house says the president was referring broadly to transformations in the region. >> there is a certain rather desperate attempt to grasp at words and phrases here to find political advantage. and in this case, that's profoundly offensive. >> reporter: the romney campaign is also posting to a clip online about the president's "60 minutes" interview, about his campaign ad. >> do we see sometimes us going overboard in our campaign, mistakes that are made or areas where there's no doubt that somebody could dispute ho